MJ-1 - Maéjima Fm (Eocene of Japan)

Where: Japan (34.6° N, 134.2° E: paleocoordinates 41.9° N, 129.4° E)

• coordinate estimated from map

• small collection-level geographic resolution

When: Maéjima Formation, Late/Upper Eocene (37.2 - 33.9 Ma)

• STRATIGRAPHIC RELATIONS: From Maéjima Fm (also referred to as Maeshima Fm) overlies pre-Tertiary plutonic rocks. THICKNESS: From bed of less than 1 m in thickness within 15 m thick section. AGE: Poorly constrained and debated, although a range of evidence points to a Late Eocene age. Sr isotopes suggest an age of Eocene or older, while foraminiferal and molluscan biostratigraphy points to an Eocene, possibly Late Eocene age. For a long time the Maéjima Fm was considered to be Miocene in age. STRATIGRAPHIC POSITION:From horizon within lower part of Maéjima Fm, immediately above basement contact.

• bed-level stratigraphic resolution

Environment/lithology: shoreface; poorly lithified, pebbly conglomerate

• ENVIRONMENT: Littoral-upper sublittoral gravelly to rocky bottom. TEMPERATURE: Warm-waters.
• SPECIFIC LITHOLOGY: Gravelly-pebbly conglomerate. LITHIFICATION: Poorly-lithified on the basis figured specimens and taphonomic comments.

Size class: macrofossils

Preservation: cast, mold/impression, original calcite

Collection methods: bulk,

• COLLECTOR: T. Matsubara. REPOSITORY: Museum of Nature and Human Activies, Hyogo, Sanda, Japan.

Primary reference: T. Matsubara. 2002. Molluscan fauna of the "Miocene" Maéjima Formation in Maéjima Island, Okayama Prefecture, southwest Japan. Paleontological Research 6(2):127-145 [A. Hendy/A. Hendy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 70910: authorized by Austin Hendy, entered by Austin Hendy on 11.04.2007

Creative Commons license: CC BY (attribution)

Taxonomic list

• COVERAGE: Exhaustive for bivalvia and gastropoda. NOMENCLATURE: Authoritative publication with current nomenclature, and species/subgenus-level assignments.
Bivalvia
 Mytilida - Mytilidae
 Ostreida - Malleidae
Isognomon (Hippochaeta) hataii Noda and Furuichi 1972 oyster